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Patent Law Basics

What is the policy rationale for patents?

A patent is a set of exclusive rights granted by a state government to an inventor or assignee for a limited period of time in exchange for detailed public disclosure of an invention. In other words, a patent is a social contract between the inventor (or assignee) and the government. The inventor or the assignee gets a monopoly for a period of time, and in return discloses the invention to the public in the published patent or patent application.

The exclusive right granted to a patentee is generally a negative right to prevent others, or at least to try to prevent others, from commercially making, using, selling, importing, or distributing a patented invention without the patentee's permission.  

What is the term of a patent?

In Canada, for patent applications filed on or after October 1, 1989, the patent expires 20 years after the patent application was filed. This is assuming that the annual maintenance fees are timely paid. If the maintenance fee is not paid, the patent will be deemed to have been abandoned.

For patent applications filed prior to October 1, 1989, the patent expires 17 years after the patent issues. 

What are the main requirements for patentability?

Not all new technologies are patentable.  In Canada, a patentable technology must be novel, non-obvious, and useful. In other words, the technology must meet the requirements of novelty, inventiveness and utility. In addition, the technology must fall within the definition of "invention" in section 2 of Canada's Patent Act.  In  section 2 of the Patent Act, "invention" is defined as any new and useful art, process, machine, manufacture or composition of matter, or any new and useful improvement in any art, process, machines, manufacture or composition of matter. The patent law in Canada expressly states that no patent shall be granted for any mere scientific principle or abstract theorem.

How is novelty assessed in Canada?

To be patentable, an invention must be novel. To be novel, the subject-matter defined by a claim in an application for a patent in Canada must not have been disclosed 
  • more than one year before the filing date by the applicant, or by a person who obtained knowledge, directly or indirectly, from the applicant, in such a manner that the subject-matter became available to the public in Canada or elsewhere; 
  • before the claim date by any third party in such a manner that the subject-matter became available to the public in Canada or elsewhere;  
  • in an application for a patent that is filed in Canada by a third party which has a filing date that is before the claim date; or 
  • in an application for a patent that is filed in Canada by a third party which has an earlier priority date.
The patent law in Canada therefore permits a one-year grace period to file a Canadian patent application after the invention is made public by the inventor. The patent law in the US also permits a one-year grace period. However, most other countries in the world do not provide any grace period.

If I file a Canadian patent application, when will it be published by the Canadian Patent Office? 

In Canada, all patent applications (except for those that are withdrawn by the applicant) are published eighteen months from the filing date or the priority date of the patent application. Published patent applications can be viewed online in the Canadian Patent Database. A goal of publication is to give the general public the ability to learn about the new technology and invention information.

Who can represent an applicant before the Canadian Patent Office?

Only a registered Canadian patent agent may represent an applicant before the Canadian Patent Office. The Canadian Patent Office maintains and publishes a list of Canadian Patent Agents who are registered with the Canadian Patent Office and who prepare and file patent applications in Canada on behalf of inventors (or assignees).

What is "double patenting" in Canada?

Section 36 of Canada's Patent Act holds that a patent is granted for “one invention only”. This has been the basis for the “double-patenting” prohibition in Canada. Double patenting holds that the claims of a later patent cannot be identical or an obvious variant of the claims of an earlier-issued patent.

Technically, double patenting can only exist between issued patents. However, in my experience, double patenting objections are often raised by examiners at the Canadian Patent Office while an application is still pending.

In Canada, divisional patent applications filed voluntarily may be susceptible to attacks on the grounds of double patenting. Unlike US patent practice, there is no terminal disclaimer practice in Canada. However, where a divisional patent application is forced by the Canadian Patent Office during prosecution (i.e. as a response to a unity of invention objection), the court has indicated that such a divisional patent application and its parent should not be open to double patenting challenges.